Heretofore, various electronic devices have been invented, and been put into practical use, but many of those conventional electronic locking devices one formed by a circuit for storing preset digits, a comparison circuit for comparing input pulses and stored digits, a coincidence circuit for detecting coincidence thereof, and an output circuit for generating an output when coincidence is obtained. Accordingly, since the conventional electronic locking device uses a large quantity of various electronic parts, it has been extremely difficult to make it into a compact size. Also, since the conventional electronic locking device needs a stable power source, the dry cell battery cannot be used from the standpoint of power consumption, and it has to be powered through a DC constant voltage power source from commercial electric power. Furthermore, since the conventional electronic locking devices are expensive because of their manufacturing cost, they can be used only in such special facilities as banks, jewelery shops, and the like and therefore they have not been widely used in ordinary households. The present invention relates to an electronic locking device which has eliminated the foregoing drawbacks of the conventional devices.